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<TITLE>[Chapter 2] 2.3 Comments</TITLE>
<META NAME="author" CONTENT="David Flanagan">
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<h2 CLASS=sect1><A CLASS="TITLE" NAME="JNUT2-CH-2-SECT-3">2.3 Comments</A></h2>

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Java supports three types of comments:

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<li CLASS=listitem>A standard C-style comment that begins with <tt CLASS=literal>/*</tt> and
continues until the next <tt CLASS=literal>*/</tt>.  As in most
implementations of C, this style of
comment cannot be nested.

<P>
<li CLASS=listitem>A C++-style comment that begins with <tt CLASS=literal>//</tt> and
continues until the end of the line.

<P>
<li CLASS=listitem>A special "doc comment" that begins with <tt CLASS=literal>/**</tt> and
continues until the next <tt CLASS=literal>*/</tt>.  These comments may not
be nested.  Doc comments are specially processed by the
<I CLASS=emphasis>javadoc</I> program to produce simple online documentation
from the Java source code.  See <A HREF="ch13_01.htm">Chapter 13, <i>Java Syntax</i></A> for
more information on the doc comment syntax, and <A HREF="ch16_01.htm">Chapter 16, <i>JDK Tools</i></A> for more information on the <I CLASS=emphasis>javadoc</I>
program.

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Since C-style comments do not nest, it is a good idea to use
C++-style <tt CLASS=literal>//</tt> comments for most of your short comments
within method bodies.  This allows you to use <tt CLASS=literal>/* */</tt>
comments to comment out large blocks of code when you need
to do that during development.  This is especially important
because, as you will see, Java does not support a
preprocessor that allows you to use <tt CLASS=literal>#if 0</tt> to
comment out a block.

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